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a(n+1) is the smallest number > a(n) such that the digits of a(n)^2 are all (with multiplicity) properly contained in the digits of a(n+1)^2, with a(0)=2.
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%I #10 Aug 26 2023 23:26:05

%S 2,7,43,136,367,1157,3658,10183,32193,101407,320537,1001842,3166463,

%T 10001923,31627114,100017313,316599084,1000104687,3162331407,

%U 10000483663

%N a(n+1) is the smallest number > a(n) such that the digits of a(n)^2 are all (with multiplicity) properly contained in the digits of a(n+1)^2, with a(0)=2.

%C a(n) for n>0 remains the same when a(0)=3.

%e 43^2 = 1849 and 136 is the next smallest number whose square (in this case 18496) properly contains the digits 1,4,8,9.

%Y Cf. A050630, A050631, A048559, A050636, A065297.

%K base,nonn,more

%O 0,1

%A _Floor van Lamoen_, Oct 29 2001

%E More terms from _Marc Paulhus_, Feb 04 2002

%E a(18)-a(19) from _Sean A. Irvine_, Aug 26 2023